Zwitterionic photo-destroyable quenchers

ABSTRACT

A photo-destroyable quencher having Formula (I): 
                         
wherein in Formula (I), groups and variables are the same as described in the specification.

FIELD

The present invention relates to photo-destroyable quenchers and theiruse in photoresist compositions.

INTRODUCTION

Advanced lithographic techniques such as electron beam and extremeultraviolet lithography have been developed to achieve high quality andsmaller feature sizes in microlithography processes, for purposes offorming ever-smaller logic and memory transistors. These advancedlithographic techniques use photoresist compositions, which ofteninclude photoacid generators. Photoacid generators generate acid onexposure to incident radiation. In exposed areas of a photoresist, thegenerated acid reacts with acid-sensitive groups in a photoresistpolymer to change the solubility of the polymer, thereby creating adifference in solubility between the exposed and unexposed regions ofthe photoresist.

Photoresists sometimes include photo-destroyable quenchers in additionto photoacid generators. Like photoacid generators, photo-destroyablequenchers generate acid in exposed areas of a photoresist, but the acidgenerated by a photo-destroyable quencher is not strong enough to reactrapidly with the acid-sensitive groups on the photoresist polymer (thisis what effectively removes the “base” component in the exposed regionbut leaves an active quencher system in the unexposed area). However, asthe strong acid generated by the photoacid generator in the exposedregion migrates to the unexposed region, the photo-destroyable quencherin the unexposed region undergoes an anion exchange, losing the anion(conjugate base) of the weak acid, and gaining the anion (conjugatebase) of the strong acid. This results in neutralization of the strongacid in the unexposed region. So, the concentration of the base islowered in the exposed region because the photo-destroyable quencher isdestroyed in that region. Accordingly, the concentration of theconjugate base anion is lower in the exposed region than in theunexposed region, which helps the image contrast.

Resist formulations containing photo destroyable quenchers are known toimprove line width roughness without sacrifice to resolution andsensitivity. Conventional photo-destroyable quenchers are sulfoniumsalts which have the same cation but a different (and much weaker)conjugate base anion from the photo acid generators in the formulation.As such, any metathesis that would occur between the two salt pairs inthe formulation would not influence the total landscape, or makeup ofthe concentration of photoacid generators versus photo-destroyablequenchers.

As feature size continues to shrink, the need for further improvement inline width roughness is desired, and scientists are beginning to lookdeeper into the photo-destroyable quencher concept for the answer. Onepotential solution to improve line width roughness might be using asulfonium photo-destroyable quencher which has a different cation andanion from the sulfonium photoacid generator. However, this presents asignificant problem as metathesis between these two salts may occurwithin the formulation, fully or partially negating the intendedindividual purpose of each compound.

Therefore, there remains a need in structurally novel photo-destroyablequenchers which can avoid salt exchange in the formulation withphotoacid generators.

SUMMARY

An embodiment provides a photo-destroyable quencher having Formula (I):

wherein

each R⁰ is attached to X, and is independently a C₁₋₃₀ alkyl group, apolycyclic or monocyclic C₃₋₃₀ cycloalkyl group, a polycyclic ormonocyclic C₆₋₃₀ aryl group, or a combination comprising at least one ofthe foregoing, provided that at least one R⁰ is a polycyclic ormonocyclic C₆₋₃₀ aryl group;

r0 is 1 or 2, provided that when X is I, r0 is 1, and when X is S, r0 is2, wherein when X is S, groups R⁰ are optionally connected to each otherso as to form a ring; and

Ar is a substituted or unsubstituted divalent C₆-C₃₀ aromatic group;

L¹ and L² are each independently a divalent C₁-C₃₀ linking groupoptionally comprising a heteroatom comprising O, S, N, F, or acombination comprising at least one of the foregoing heteroatoms;

M is a substituted or unsubstituted, divalent C₅-C₃₀ or greatermonocyclic, polycyclic, or fused polycyclic cycloaliphatic group,optionally comprising a heteroatom comprising O, S, N, F, or acombination comprising at least one of the foregoing;

Y is an oxygen-containing anionic group; and

l₁, l₂, and m are each independently an integer of 0 or 1.

Another embodiment provides a composition including the compoundincluding:

an acid-sensitive polymer;

a photoacid generator; and

a photo-destroyable quencher having Formula (I).

Still another embodiment provides a coated substrate including: (a) asubstrate having one or more layers to be patterned on a surfacethereof; and (b) a layer of the composition disposed over the one ormore layers to be patterned.

Yet another embodiment provides a method of making a relief image, themethod including:

coating a substrate having a layer comprising a photoacid generator anda photo-destroyable quencher having Formula (I),

pattern-wise exposing the composition layer to radiation; and

developing the pattern by treatment with an aqueous alkaline developerto form a positive tone relief image, or with an organic solventdeveloper to form a negative tone relief image.

DETAILED DESCRIPTION

Reference will now be made in detail to the exemplary embodiments,examples of which are illustrated in the accompanying drawings, whereinlike reference numerals refer to like elements throughout. In thisregard, the present exemplary embodiments may have different forms andshould not be construed as being limited to the descriptions set forthherein. Accordingly, the exemplary embodiments are merely describedbelow, by referring to the figures, to explain aspects of the presentinventive concept. As used herein, the term “and/or” includes any andall combinations of one or more of the associated listed items.Expressions such as “at least one of,” when preceding a list ofelements, modify the entire list of elements and do not modify theindividual elements of the list.

It will be understood that when an element is referred to as being “on”another element, it can be directly in contact with the other element orintervening elements may be present therebetween. In contrast, when anelement is referred to as being “directly on” another element, there areno intervening elements present.

It will be understood that, although the terms first, second, third,etc., may be used herein to describe various elements, components,regions, layers, and/or sections, these elements, components, regions,layers, and/or sections should not be limited by these terms. Theseterms are only used to distinguish one element, component, region,layer, or section from another element, component, region, layer, orsection. Thus, a first element, component, region, layer, or sectiondiscussed below could be termed a second element, component, region,layer, or section without departing from the teachings of the presentembodiments.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms “comprises” and/or“comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and thepresent disclosure, and will not be interpreted in an idealized oroverly formal sense unless expressly so defined herein.

As used herein, when a definition is not otherwise provided, the term“alkyl group” refers to a group derived from a straight or branchedchain saturated aliphatic hydrocarbon having the specified number ofcarbon atoms and having a valence of at least one.

As used herein, when a definition is not otherwise provided, the term“fluoroalkyl group” refers to an alkyl group in which at least onehydrogen atom is replaced with a fluorine atom.

As used herein, when a definition is not otherwise provided, the term“alkoxy group” refers to “alkyl-O—”, wherein the term “alkyl” has thesame meaning as described above.

As used herein, when a definition is not otherwise provided, the term“fluoroalkoxy group” refers to an alkoxy group in at least one hydrogenatom that is replaced with a fluorine atom.

As used herein, when a definition is not otherwise provided, the term“alkenyl group” refers to a group derived from a straight or branchedchain unsaturated aliphatic hydrocarbon having the specified number ofcarbon atoms and having a valence of at least one.

As used herein, when a definition is not otherwise provided, the term“cycloalkyl group” refers to a monovalent group having one or moresaturated rings in which all ring members are carbon.

As used herein, when a definition is not otherwise provided, the term“fluorocycloalkyl group” refers to a cycloalkyl group in which at leastone hydrogen atom is replaced with a fluorine atom.

As used herein, when a definition is not otherwise provided, the term“aryl group”, which is used alone or in combination, refers to anaromatic hydrocarbon containing at least one ring and having thespecified number of carbon atoms. The term “aryl” may be construed asincluding a group with an aromatic ring fused to at least one cycloalkylring.

As used herein, when a definition is not otherwise provided, the term“aralkyl group” refers to a substituted or unsubstituted aryl groupcovalently linked to an alkyl group that is linked to a compound,wherein the terms “aryl” and “alkyl” have the same meaning as describedabove.

As used herein, when a definition is not otherwise provided, the term“substituted” means including at least one substituent such as a halogen(F, Cl, Br, I), hydroxyl, amino, thiol, carboxyl, carboxylate, ester(including acrylates, methacrylates, and lactones), amide, nitrile,sulfide, disulfide, nitro, C₁₋₂₀ alkyl, C₁₋₂₀ cycloalkyl (includingadamantyl), C₁₋₂₀ alkenyl (including norbornenyl), C₁₋₂₀ alkoxy, C₂₋₂₀alkenoxy (including vinyl ether), C₆₋₃₀ aryl, C₆₋₃₀ aryloxy, C₇₋₃₀alkylaryl, or C₇₋₃₀ alkylaryloxy.

When a group containing a specified number of carbon atoms issubstituted with any of the groups listed in the preceding paragraphs,the number of carbon atoms in the resulting “substituted” group isdefined as the sum of the carbon atoms contained in the original(unsubstituted) group and the carbon atoms (if any) contained in thesubstituent. For example, when the term “substituted C₁-C₂₀ alkyl”refers to a C₁-C₂₀ alkyl group substituted with C₆-C₃₀ aryl group, thetotal number of carbon atoms in the resulting aryl substituted alkylgroup is C₇-C₅₀.

As used herein, when the definition is not otherwise provided, the term“mixture” refers to any combination of the ingredients constituting theblend or mixture without regard to a physical form.

As noted above, there is currently a need in structurally novelphoto-destroyable quenchers which can avoid salt exchange in theformulation with photoacid generators. The current invention presentsnovel photo-destroyable quenchers which have the anion and cationcovalently bound to each other to form a zwitterionic species or a“fused photo-destroyable quenchers”. These novel photo-destroyablequenchers are unable to undergo salt exchange with any other salt(namely, the sulfonium or iodonium photoacid generator) in aformulation. This novel technology allows for both the cation and anionof a given photo-destroyable quencher to be optimized for a specificpurpose/formulation without sacrifice to the integrity of the photoacidgenerator in a given system.

Disclosed herein is a zwitterionic photo-destroyable quencherrepresented by Formula (I):

In Formula (I), X may be sulfur (S) or iodine (I). Groups R⁰ may be thesame or different, and may each independently be a C₁₋₃₀ alkyl group, apolycyclic or monocyclic C₃₋₃₀ cycloalkyl group, a polycyclic ormonocyclic C₆₋₃₀ aryl group, or a combination comprising at least one ofthe foregoing, provided that at least one R⁰ is a polycyclic ormonocyclic C₆₋₃₀ aryl group.

r0 may be 1 or 2. When, X is I, r0 is 1. When X is S, r0 is 2. When X isS, one of R⁰ may be a polycyclic or monocyclic C₆₋₃₀ aryl group, whilethe other one of R⁰ may be a C₁₋₃₀ alkyl group, a polycyclic ormonocyclic C₃₋₃₀ cycloalkyl group, or a polycyclic or monocyclic C₆₋₃₀aryl group. When X is S, groups R⁰ may be optionally connected to eachother so as to form a ring. In an embodiment, each R⁰ may be apolycyclic or monocyclic C₆₋₃₀ aryl group.

Ar may be a substituted or unsubstituted divalent C₆-C₃₀ aromatic group.The divalent C₆-C₃₀ aromatic group may include a single aromatic ring ormore than one aromatic ring. When the divalent C₆-C₃₀ aromatic groupincludes more than one aromatic ring, the rings may be fused or may beconnected by a single bond. In an embodiment, Ar may be a substituted orunsubstituted phenylene group.

The zwitterionic photo-destroyable quencher represented by Formula (I)may further include linking groups L¹, M, and L².

L¹ and L² may each independently be a divalent C₁-C₃₀ linking group, andmay include a heteroatom selected from O, S, N, F, or a combination ofat least one of these heteroatoms. When l1 is 1, the linking group L¹ ispresent. When l1 is 0, the linking group L¹ is absent. When L¹ isabsent, group Ar may be directly connected to the linking group M via asingle bond. Likewise, when l2 is 1, the linking group L² is present.When l2 is 0, the linking group L² is absent. When L² is absent, groupAr may be directly connected to the linking group M via a single bond.In an embodiment, L¹ and L² may each independently be a divalent C₁-C₃₀linking group including an —O—, —C(═O)—O—, —O—C(═O)—, —C(═O)—NR—, or—O—C(═O)—NR— moiety, wherein R is H or a substituted or unsubstitutedC₁-C₅ alkyl group. In another embodiment, group L² may include asubstituted or unsubstituted C₁₋₃₀ alkylene group, a substituted orunsubstituted C₆₋₃₀ arylene group, a substituted or unsubstituted C₇₋₃₀aralkylene group, or a combination comprising at least one of theforegoing groups.

The linking group M may be a substituted or unsubstituted, divalentC₅-C₃₀ or greater monocyclic, polycyclic, or fused polycycliccycloaliphatic group, and may optionally include a heteroatom selectedfrom O, S, N, F, or a combination including at least one of theforegoing heteroatoms. In an embodiment, group M may be a C₁₉ or lessadamantyl group, a C₁₉ or less norbornanyl group, a C₇₋₂₀lactone-containing group, a C₂₀ steroidal group, or C₂₀ or greaternon-steroidal organic group. When m is 0, the linking group M is absent.When M is absent, the linking group L¹ may be directly connected to thelinking group L² via a single bond. When l1 is 0 and m is 0, group Armay be directly connected to the linking group L² via a single bond.

The zwitterionic photo-destroyable quencher represented by Formula (I)further includes group Y, which is an oxygen-containing anionic group.In an embodiment, Y may be C(═O)O, O, SO₂NH, or SO₃. For example, Y maybe C(═O)O or O. When m is 0 and l2 is 0, the linking group L¹ may bedirectly connected to the anionic group Y via a single bond. When l1 is0, m is 0, and l2 is 0, group Ar may be directly connected to theanionic group Y via a single bond.

In an embodiment, l₁ may be 0, l₂ may be 0, and m may be 0. In anotherembodiment, l₁ may be 1, l₂ may be 0 or 1, and m may be 0. In yetanother embodiment, l₁ may be 1, l₂ may be 1, and m may be 1.

The compound of Formula (I) may be a sulfonium zwitterion represented byFormula (II):

In Formula (II), each R⁰ may be independently a C₁₋₃₀ alkyl group, apolycyclic or monocyclic C₃₋₃₀ cycloalkyl group, a polycyclic ormonocyclic C₆₋₃₀ aryl group, or a combination comprising at least one ofthe foregoing, provided that at least one R⁰ is a polycyclic ormonocyclic C₆₋₃₀ aryl group. Two groups R⁰ may be optionally connectedto each other as to form a ring. In Formula (II), groups Ar, L¹, L², M,X, and variables l1, l2, and m may be the same as described above inconnection with Formula (I).

The compound of Formula (I) may be an iodonium zwitterion represented byFormula (V):

In Formula (V), R⁰ may be a polycyclic or monocyclic C₆₋₃₀ aryl group.In Formula (V), groups Ar, L¹, L², M, X, and variables l1, l2, and m maybe the same as described above in connection with Formula (II).

In an embodiment, the photo-destroyable quencher having Formula (I) maybe represented by Formula (III) or Formula (IV):

In Formula (III), two aromatic rings of the sulfonium cation areconnected through a linker K. In an embodiment, K may be a single bond.In another embodiment, K may be a divalent connecting group selectedfrom S, O, NR (wherein R is H or a substituted or unsubstituted C₁-C₅alkyl group), S(═O), S(═O)₂, C(═O), C(═O)O, OC(═O), a substituted orunsubstituted C₁-C₅ alkylene group, or a combination thereof.

The aromatic rings of the constrained sulfonium cation may besubstituted or unsubstituted with groups R¹ and R². R¹ and R² may eachindependently be a halogen, —CN, —OH, a C₁₋₁₀ alkyl group, a C₁₋₁₀fluoroalkyl group, a C₁₋₁₀ alkoxy group, a C₁₋₁₀ fluoroalkoxy group, aC₃₋₁₀ cycloalkyl group, a C₃₋₁₀ fluorocycloalkyl group, a C₃₋₁₀cycloalkoxy group, or a C₃₋₁₀ fluorocycloalkoxy group, each of whichexcept a halogen, —CN, and —OH is substituted or unsubstituted, whereintwo adjacent groups R¹ or two adjacent groups R² may optionally form aring. Groups R¹ and R² are absent when r1 is 0 and r2 is 0. In someembodiments, the aromatic rings of the constrained sulfonium cation mayinclude 1 to 4 groups R¹ and R². Thus, in Formula (II), r1 and r2 mayeach independently be 0, 1, 2, 3, or 4.

Formula (IV) represents an open sulfonium cation, in which two aromaticrings are not connected to each other. The aromatic rings of the opensulfonium cation may be substituted or unsubstituted with groups R³ andR⁴. R³ and R⁴ may each independently be a halogen, —CN, —OH, a C₁₋₁₀alkyl group, a C₁₋₁₀ fluoroalkyl group, a C₁₋₁₀ alkoxy group, a C₁₋₁₀fluoroalkoxy group, a C₃₋₁₀ cycloalkyl group, a C₃₋₁₀ fluorocycloalkylgroup, a C₃₋₁₀ cycloalkoxy group, or a C₃₋₁₀ fluorocycloalkoxy group,each of which except a halogen, —CN, and —OH is substituted orunsubstituted, wherein two adjacent groups R³ or two adjacent groups R⁴may optionally form a ring. Groups R³ and R⁴ are absent when r3 is 0 andr4 is 0. In some embodiments, the aromatic rings of the constrainedsulfonium cation may include 1 to 5 groups R³ and R⁴. Thus, in Formula(II), r3 and r4 may each independently be 0, 1, 2, 3, 4, or 5.

Specific examples of the photo-destroyable quenchers may include:

The photo-destroyable quencher according to the embodiments of thepresent invention can be formulated with a photoacid generator. Thephotoacid generator may be any suitable compound known in the art. Forexample, the photoacid generator may be a compound having Formula (VI):G⁺Z⁻  Formula (VI)wherein G has the Formula (VII):

In Formula (VII), X may be S or I. Each R⁰ is attached to X and mayindependently be a C₁₋₃₀ alkyl group; a polycyclic or monocyclic C₃₋₃₀cycloalkyl group; a polycyclic or monocyclic C₆₋₃₀ aryl group; or acombination comprising at least one of the foregoing. r5 may be 2 or 3,provided that when X is I, r5 is 2, and when X is S, r5 is 2 or 3. InFormula (VI), Z may include the anion of a sulfonic acid, a sulfonimide,or a sulfonamide.

The composition may further include a polymer and a solvent to form aphotoresist composition. The polymer may be an acid-sensitive polymer.Where the combination is a polymer bound photoacid generator, anappropriately functionalized photoacid generator can be copolymerizedwith one or more monomers to form the copolymer, or the photoacidgenerator can be grafted onto the copolymer.

A copolymer useful for forming a photoresist in combination with thephotoacid generator disclosed herein may include an acid-deprotectable(acid-sensitive) monomer, a base-soluble monomer, a dissolution ratemodifying monomer, and an etch resistant monomer. Any such monomers orcombinations of monomers are suitable for forming, for example, a 193 nmphotoresist polymer. In an embodiment, a combination of monomers may beused, which include a (meth)acrylate monomer having anacid-deprotectable base soluble group, a (meth)acrylate monomer having alactone functional group, a (meth)acrylate monomer having a base-solublegroup, or a combination including at least one of the foregoingmonomers. Other monomers, such as (meth)acrylate monomer for improvingadhesion, etch resistance, and so on, may also be included.

Any acid-deprotectable monomer useful for forming a 193 nm photoresistpolymer may be used. Exemplary acid-deprotectable monomers include, butare not limited to:

or a combination comprising at least one of the foregoing monomers,wherein R^(a) is H, F, CN, C₁₋₁₀ alkyl, or C₁₋₁₀ fluoroalkyl.

Any lactone-containing monomer useful for forming a 193 nm photoresistpolymer may be used. Exemplary lactone-containing monomers include, butare not limited to:

or a combination including at least one of the foregoing monomers,wherein R^(a) is H, F, CN, a C₁₋₁₀ alkyl group, or a C₁₋₁₀ fluoroalkylgroup.

Any base-soluble monomer useful for forming a 193 nm photoresist polymermay be used. Exemplary additional base-soluble (meth)acrylate monomersinclude, but are not limited to:

or a combination including at least one of the foregoing monomers,wherein R^(a) is H, F, CN, a C₁₋₁₀ alkyl group, or a C₁₋₁₀ fluoroalkylgroup, and R^(c) is a C₁₋₄ perfluoroalkyl group.

The polymer may also include other monomers, including cage-structuredmonomers for enhancing etch resistance, with or without functionalgroups for improving adhesion. An exemplary adhesion-improving monomermay include:

or a combination comprising the foregoing and at least one additionalmonomer, wherein R^(a) is H, C₁₋₆ alkyl, or CF₃.

The photoacid generator may be combined with the copolymer, either inadmixture, by copolymerization or both, to form a photoresist. Thephotoresist may optionally further include a second acid sensitivepolymer and/or photoacid generator, an amine or an amide additive toadjust photospeed and/or acid diffusion, a solvent, and a surfactant.

The second acid-sensitive polymer may be any polymer suitable forformulating photoresists for use at 193 nm. Such acid-sensitive polymersmay include an acid sensitive polymer including acid sensitive groupsand lactone-containing groups, wherein the deprotection of the acidsensitive group on exposure to acid releases a base-soluble group. Theacid-sensitive polymer may be a polymer-bound photoacid generator (PBP)wherein the photoacid generator repeat unit is an anion or a cation.

The photoresist composition may further include an amine or amidecompound, referred to herein as a quencher. Quenchers may more broadlyinclude, for example, compounds which are hydroxides, carboxylates,amines, imines, and amides. In an embodiment, a useful quencher is anamine, an amide, or a combination comprising at least one of theforegoing. For example, such quenchers may include C₁₋₃₀ organic amines,imines, or amides, or may be a C₁₋₃₀ quaternary ammonium salt of astrong base (for example, a hydroxide or alkoxide) or a weak base (forexample, a carboxylate). Exemplary quenchers may include amines such asTroger's base, a hindered amine such as diazabicycloundecene (DBU) ordiazabicyclononene (DBN), N-protected amines such asN-t-butylcarbonyl-1,1-bis(hydroxymethyl)-2-hydroxyethylamine(TBOC-TRIS), or ionic quenchers including quaternary alkyl ammoniumsalts such as tetrabutylammonium hydroxide (TBAH) or tetrabutyl ammoniumlactate.

Other components of the photoresist may include solvents andsurfactants.

Solvents generally suitable for dissolving, dispensing, and coating thecomponents may include anisole, alcohols including ethyl lactate, methyl2-hydroxybutyrate (HBM), 1-methoxy-2-propanol (also referred to aspropylene glycol methyl ether, PGME), and 1-ethoxy-2 propanol, estersincluding n-butylacetate, 1-methoxy-2-propyl acetate (also referred toas propylene glycol methyl ether acetate, PGMEA),methoxyethoxypropionate, ethoxyethoxypropionate, andgamma-butyrolactone, ketones including cyclohexanone and 2-heptanone,and a combination comprising at least one of the foregoing solvents.

Surfactants may include fluorinated and non-fluorinated surfactants, andmay, for example, be non-ionic. Exemplary fluorinated non-ionicsurfactants may include perfluoro C₄ surfactants such as FC-4430 andFC-4432 surfactants, available from 3M Corporation; and fluorodiols suchas POLYFOX PF-636, PF-6320, PF-656, and PF-6520 fluorosurfactants fromOmnova.

The photo-destroyable quencher may be present in the photoresist in anamount of 0 to 20 percent by weight (wt %), for example, 1 to 5 wt %,based on the total weight of the solids. The photoacid generator may bepresent in the photoresist in an amount of 0.01 to 35 wt %, for example,0.1 to 20 wt %, based on the total weight of the solids. Where a polymerbound photoacid generator is used, the polymer bound photoacid generatoras the corresponding monomer is present in the same amount. Thecopolymer may be present in an amount of 50 to 99 wt %, for example, 55to 95 wt %, in another example, 60 to 90 wt %, and in still anotherexample, 65 to 90 wt % based on the total weight of the solids. It willbe understood that the term “polymer” used in this context of acomponent in a photoresist may mean only the copolymer disclosed herein,or a combination of the polymer with another polymer useful in aphotoresist. A surfactant may be included in an amount of 0.01 to 5 wt%, for example, 0.1 to 4 wt %, and in another example, 0.2 to 3 wt %,based on the total weight of the solids. A quencher may be included in arelatively small amount of, for example, from 0.03 to 5 wt % based onthe total weight of the solids. Other additives such as embedded barrierlayer (EBL) materials for immersion lithography applications may beincluded in amounts of less than or equal to 30 wt %, for example, lessthan or equal to 20%, or in another example, less than or equal to 10%,based on the total weight of the solids. The total solids content forthe photoresist composition may be 0.5 to 50 wt %, for example, 1 to 45wt %, and in another example, 2 to 40 wt %, and still in anotherexample, 5 to 35 wt %, based on the total weight of the solids andsolvent. It will be understood that the solids may include a copolymer,a photoacid generator, a quencher, a surfactant, and any optionaladditives, exclusive of the solvent.

The photoresist composition disclosed herein may be used to form a filmcomprising the photoresist composition, where the film on the substrateconstitutes a coated substrate. Such a coated substrate may include: (a)a substrate having one or more layers to be patterned on a surfacethereof, and (b) a layer of the photoresist composition over the one ormore layers to be patterned. For example, patterning may be carried outusing ultraviolet radiation at a wavelength of less than 248 nm, and inparticular, at 193 nm. The patternable film thus includes the photoacidgenerator of Formula (I).

A method of forming an electronic device therefore includes: (a) coatinga substrate having a layer comprising a polymer (which may be anacid-sensitive polymer), a photoacid generator, and a photo-destroyablequencher having Formula (I); (b) pattern-wise exposing the photoresistcomposition layer to activating radiation; and (c) developing theexposed photoresist composition layer to provide a resist relief image.For example, the radiation is 193 nm or 248 nm radiation.

Substrates may be of any dimension and shape, and may, for example, bethose useful for photolithography, such as silicon, silicon dioxide,silicon-on-insulator (SOI), strained silicon, gallium arsenide, coatedsubstrates including those coated with silicon nitride, siliconoxynitride, titanium nitride, tantalum nitride, ultrathin gate oxidessuch as hafnium oxide, metal or metal coated substrates including thosecoated with titanium, tantalum, copper, aluminum, tungsten, alloysthereof, and combinations thereof. For example, the surfaces ofsubstrates herein include critical dimension layers to be patternedincluding, for example, one or more gate-level layers or other criticaldimension layer on the substrates for semiconductor manufacture. Suchsubstrates may, for example, include silicon, SOI, strained silicon, andother such substrate materials, formed as circular wafers havingdimensions such as, for example, 200 mm, 300 mm, or larger in diameter,or other dimensions useful for wafer fabrication production.

The novel fused photo-destroyable quenchers may be synthesized utilizingthe corresponding oxygen-containing anions to form the zwitterionicspecies with the sulfonium cation. In this method, a sulfonium bromideor iodide which is composed of either a benzoic acid, sulfonic acid, orphenolic moiety may be exposed to silver oxide in a solvent. Afterneutralization of the acidic species (carboxylic acid, sulfonic acid, orphenol) and precipitation of silver bromide/iodide, the fusedphoto-destroyable quenchers may be easily isolated by filtration andsolvent removal. Each of these synthetic routes (carboxylic acid,sulfonic acid, or phenol) are robust, scalable, and may be applicable toa variety of compounds contain a benzoic acid, a sulfonic acid, orphenolic moiety.

The present inventive concept is further illustrated by the followingexamples. All compounds and reagents used herein are availablecommercially except where a procedure is provided below.

EXAMPLES Example 1:3-(5H-Dibenzo[b,d]thiophenium-5-yl)-4-methoxybenzoate

A mixture of 5-(5-carboxy-2-methoxyphenyl)-5H-dibenzo[b,d]thiopheniumiodide (1.00 g, 2.16 mmol) and silver oxide (2.16 mmol, 0.251 g) wasdissolved in methanol (30 mL) and stirred at room temperature overnight.The precipitate was filtered and the methanol was concentrated. Theresidue was diluted with methanol (30 mL) and concentrated. The productwas precipitated from methyl tert-butyl ether (MTBE) to afford the titlecompound (0.723 g, 84%) as a white solid.

1H NMR (500 MHz, (CD₃)₂CO) δ (ppm): 8.39 (d, J=8 Hz, 2H), 8.25 (dt, J=8,1.5 Hz, 1H), 8.17 (d, J=8 Hz, 2H), 7.94 (t, J=7.5 Hz, 2H), 7.71-7.77 (m,3H), 7.32 (dd, J=8.5, 1.5 Hz, 1H), 3.99 (s, 3H).

Example 2: 4-(Diphenylsulfonio)phenolate

A mixture of (4-hydroxyphenyl)diphenylsulfonium iodide (1.00 g, 2.46mmol) and silver oxide (2.46 mmol, 0.285 g) were dissolved in methanol(30 mL) and stirred at room temperature overnight. The precipitate wasfiltered and the methanol was concentrated. The residue was diluted withmethanol (30 mL) and concentrated. The product was precipitated from amixture of MTBE and heptane to afford the title compound (0.690 g, 100%)as a hydroscopic white solid.

1H NMR (500 MHz, (CD₃)₂CO) δ (ppm): 7.58-7.78 (m, 10H), 7.17 (dd, J=9.5,2 Hz, 2H), 6.18 (dd, J=9, 2 Hz, 2H).

Example 3: Preparation of Polymer with Acid Generator Units

The heel solution was made by dissolving 2-phenylpropan-2-ylmethacrylate (0.39 g), 2-oxotetrahydrofuran-3-yl methacrylate (0.33 g),3,5-bis(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)cyclohexylmethacrylate (0.57 g) and5-(4-(2-(1-ethylcyclopentyloxy)-2-oxoethoxy)-3,5-dimethylphenyl)-5H-dibenzo[b,d]thiophenium1,1-difluoro-2-(methacryloyloxy)ethanesulfonate (0.31 g) in 12.81 gacetonitrile/tetrahydrofuran (2/1 volume to volume, v/v). The feedsolution was prepared by dissolving 2-phenylpropan-2-yl methacrylate(185.54 g, 0.967 mol), 2-oxotetrahydrofuran-3-yl methacrylate (204.27 g,1.26 mol),3,5-bis(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)cyclohexylmethacrylate (127.98 g, 0.29 mol) and5-(4-(2-(1-ethylcyclopentyloxy)-2-oxoethoxy)-3,5-dimethylphenyl)-5H-dibenzo[b,d]thiophenium1,1-difluoro-2-(methacryloyloxy)ethanesulfonate (81.5 g, 0.132 mol) in606 g ethyl lactate: γ-butyryl lactone (30/70 v/v). The initiatorsolution was prepared by dissolving 65.96 g initiator (V-65) in 66 gacetonitrile/tetrahydrofuran (2/1 v/v). The polymerization was carriedout in a 2 L 3-neck round bottom flask fitted with a water condenser anda thermometer to monitor the reaction in the flask. The contents werestirred using an overhead stirrer. The reactor was charged with the heelsolution and the contents were heated to 75° C. The feed solution andthe initiator solution were fed into the reactor using syringe pump overa 4 hour time period. The contents were then stirred for additional 2hours, whereby, the reaction was quenched using hydroquinone (2.0 g).The contents were cooled to room temperature and precipitated twice outof 10-fold excess (by weight) IPE/MeOH 95/5 (weight to weight, w/w). Thepolymer obtained was dried in vacuo after each precipitation step at 50°C. for 24 hours to yield 500 g of the polymer.

Example 4: Preparation of Polymer with Acid Generator Units

The same process and mole ratio used in Example 3 was used in thepreparation of the polymer in the present example, except5-(phenyl)-5H-dibenzo[b,d]thiophenium1,1-difluoro-2-(methacryloyloxy)ethanesulfonate was used in place of5-(4-(2-(1-ethylcyclopentyloxy)-2-oxoethoxy)-3,5-dimethylphenyl)-5H-dibenzo[b,d]thiophenium1,1-difluoro-2-(methacryloyloxy)ethanesulfonate:

Example 5: Preparation of Photoacid Generator

5-(4-(2-(1-ethylcyclopentyloxy)-2-oxoethoxy)-3,5-dimethylphenyl)-5H-dibenzo[b,d]thiopheniumbromide (2.00 g, 3.71 mmol) and sodium3-hydroxyadamantane-acetoxy-1,1,2,2-tetrafluorobutane-1-sulfonate (1.61g, 3.78 mmol) were dissolved in dichloromethane (100 mL) and water (100mL) and stirred at room temperature overnight. The dichloromethane layerwas separated and the aqueous phase was washed with dichloromethane(3×100 mL). The combined organic layers were washed with water (4×200mL), concentrated in vacuo and residual water was removed via azeotropewith acetonitrile (2×200 mL) to afford the title compound (2.90 g, 91%)as a white solid.

¹H NMR (500 MHz, (CD₃)₂CO) δ: 8.52 (d, J=8 Hz, 2H), 8.34 (d, J=8.5 Hz,2H), 8.01 (t, J=7.5 Hz, 2H), 7.08 (t, J=7.5 Hz, 2H), 7.51 (s, 2H), 4.55(s, 2H), 4.32 (t, J=6.5 Hz, 2H), 3.60 (br s, OH), 2.72 (tt, J=14, 6.5Hz, 2H), 2.29 (s, 6H), 2.12-2.20 (m, 2H), 2.00 (q, J=7 Hz, 2H),1.50-1.82 (m, 12H), 0.84 (t, J=7 Hz, 3H).

Example 6: Photoresist Formulation Including Photo-Destroyable Quencher

A positive-tone photoresist composition was prepared by combining 10.297g of a 10 wt % solution of the polymer obtained in Example 4 in ethyllactate, 10.047 g of a 2 wt % solution of the acid listed in Example 5in ethyl lactate, 0.586 g of a 0.5 wt % solution oftetrakis(2-hydroxypropyl)ethylenediamine in ethyl lactate, 0.945 g of a2 wt % solution of the compound prepared as described in Example 1 inethyl lactate, 0.206 g of a 0.5 wt % solution of fluorinated surfactant(Omnova PF656) in ethyl lactate, 13.005 g of ethyl lactate and 14.625 gof 2-hydroxyisobutyric acid methyl ester. The formulated resist waspassed through a 0.01 μm PTFE filter. The prepared resist is spin coatedonto a silicon wafer, soft baked to remove carrier solvent and exposedthrough a photomask to EUV radiation. The imaged resist layer is thenbaked at 110° C. for 60 seconds and then developed with an aqueousalkaline composition.

Comparative Example: Photoresist Formulation without Photo-DestroyableQuencher

A positive-tone photoresist composition was prepared by combining 10.297g of a 10 wt % solution of the polymer obtained in Example 4 in ethyllactate, 10.047 g of a 2 wt % solution of the acid listed in Example 5in ethyl lactate, 0.586 g of a 0.5 wt % solution oftetrakis(2-hydroxypropyl)ethylenediamine in ethyl lactate, 0.206 g of a0.5 wt % solution of fluorinated surfactant (Omnova PF656) in ethyllactate, 13.005 g of ethyl lactate and 14.625 g of 2-hydroxyisobutyricacid methyl ester. The formulated resist was passed through a 0.01 μmPTFE filter. The prepared resist is spin coated onto a silicon wafer,soft baked to remove carrier solvent and exposed through a photomask toEUV radiation. The imaged resist layer is then baked at 110° C. for 60seconds and then developed with an aqueous alkaline composition.

The data comparing E-size and local critical dimension uniformity (LCDU)number of the formulations prepared according to Example 5 andComparative Example are summarized in Table 1.

E-size LCDU (mJ/cm²) (nm) Comparative Example

Example 6 ● ♦ wherein 

 is reference, ● is improvement by >10%, and ♦ is the same as reference.

It was found that the E-size value of the formulation including thephoto-destroyable quencher (Example 6) was improved by 10% compared tothat value of the formulation having no photo-destroyable quencher(Comparative Example). This improvement was achieved without sacrificingthe LCDU value of the formulation.

While this disclosure has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

The invention claimed is:
 1. A photo-destroyable quencher having Formula(I):

wherein X is S or I, each R⁰ is attached to X, and is independently aC₁₋₃₀ alkyl group, a polycyclic or monocyclic C₃₋₃₀ cycloalkyl group, apolycyclic or monocyclic C₆₋₃₀ aryl group, or a combination comprisingat least one of the foregoing, provided that at least one R⁰ is apolycyclic or monocyclic C₆₋₃₀ aryl group; r0 is 1 or 2, provided thatwhen X is I, r0 is 1, and when X is S, r0 is 2, wherein when X is S,groups R⁰ are optionally connected to each other so as to form a ring;and Ar is a substituted or unsubstituted divalent C₆-C₃₀ aromatic group;L¹ and L² are each independently a divalent C₁-C₃₀ linking groupoptionally comprising a heteroatom comprising O, S, N, F, or acombination comprising at least one of the foregoing heteroatoms; M is asubstituted or unsubstituted, divalent C₅-C₃₀ or greater monocyclic,polycyclic, or fused polycyclic cycloaliphatic group, optionallycomprising a heteroatom comprising O, S, N, F, or a combinationcomprising at least one of the foregoing; Y is an oxygen-containinganionic group, provided that when X is S, Y is C(═O)O, O, or SO₂NH; andl₁, l₂, and m are each independently an integer of 0 or
 1. 2. Thephoto-destroyable quencher according to claim 1, wherein the compound ofFormula (I) is represented by Formula (II):

wherein each R⁰ is independently a C₁₋₃₀ alkyl group, a polycyclic ormonocyclic C₃₋₃₀ cycloalkyl group, a polycyclic or monocyclic C₆₋₃₀ arylgroup, or a combination comprising at least one of the foregoing,provided that at least one R⁰ is a polycyclic or monocyclic C₆₋₃₀ arylgroup; groups R⁰ are optionally connected to each other so as to form aring; and Ar is a substituted or unsubstituted divalent C₆-C₃₀ aromaticgroup; L¹ and L² are each independently a divalent C₁-C₃₀ linking groupoptionally comprising a heteroatom comprising O, S, N, F, or acombination comprising at least one of the foregoing heteroatoms; M is asubstituted or unsubstituted, divalent C₅-C₃₀ or greater monocyclic,polycyclic, or fused polycyclic cycloaliphatic group, optionallycomprising a heteroatom comprising O, S, N, F, or a combinationcomprising at least one of the foregoing; Y is C(═O)O, O, or SO₂NH; andl₁, l₂, and m are each independently an integer of 0 or
 1. 3. Thephoto-destroyable quencher according to claim 2, wherein each R⁰ is apolycyclic or monocyclic C₆₋₃₀ aryl group.
 4. The photo-destroyablequencher according to claim 1, wherein the photo-destroyable quencherhaving Formula (I) is represented by Formula (III) or Formula (IV):

wherein K is a single bond or a divalent connecting group selected fromS, O, NR (wherein R is H or a substituted or unsubstituted C₁-C₅ alkylgroup), S(═O), S(═O)₂, C(═O), C(═O)O, OC(═O), a substituted orunsubstituted C₁-C₅ alkylene group, or a combination thereof; Ar is asubstituted or unsubstituted divalent C₆-C₃₀ aromatic group; L¹ and L²are each independently a divalent C₁-C₃₀ linking group optionallycomprising a heteroatom comprising O, S, N, F, or a combinationcomprising at least one of the foregoing heteroatoms; M is a substitutedor unsubstituted, divalent C₅-C₃₀ or greater monocyclic, polycyclic, orfused polycyclic cycloaliphatic group, optionally comprising aheteroatom comprising O, S, N, F, or a combination comprising at leastone of the foregoing; Y is C(═O)O, O, or SO₂NH; R¹ to R⁴ are eachindependently a halogen, —CN, —OH, a C₁₋₁₀ alkyl group, a C₁₋₁₀fluoroalkyl group, a C₁₋₁₀ alkoxy group, a C₁₋₁₀ fluoroalkoxy group, aC₃₋₁₀ cycloalkyl group, a C₃₋₁₀ fluorocycloalkyl group, a C₃₋₁₀cycloalkoxy group, or a C₃₋₁₀ fluorocycloalkoxy group, each of whichexcept a halogen, —CN, and —OH is substituted or unsubstituted, whereintwo adjacent R¹, two adjacent R², two adjacent R³, or two adjacent R⁴optionally form a ring; l₁, l₂, and m are each independently an integerof 0 or 1; r₁ and r₂ are each independently an integer of 0 to 4; and r₃and r₄ are each independently an integer of 0 to
 5. 5. Thephoto-destroyable quencher according to claim 1, wherein Ar is asubstituted or unsubstituted phenylene group.
 6. The photo-destroyablequencher according to claim 1, wherein when X is I, Y is C(═O)O, O,SO₂NH, or SO₃.
 7. The photo-destroyable quencher according to claim 1,wherein L¹ and L² are each independently a divalent C₁-C₃₀ linking groupcomprising an —O—, —C(═O)—O—, —O—C(═O)—, —C(═O)—NR—, or —O—C(═O)—NR—moiety, wherein R is H or a substituted or unsubstituted C₁-C₅ alkylgroup.
 8. The photo-destroyable quencher according to claim 1, wherein Mis a C₁₉ or less adamantyl group, a C₁₉ or less norbornanyl group, aC₇₋₂₀ lactone-containing group, a C₂₀ steroidal group, or C₂₀ or greaternon-steroidal organic group.
 9. The photo-destroyable quencher accordingto claim 1, wherein (i) l₁ is 0, l₂ is 0, and m is 0; (ii) l₁ is 1, l₂is 0 or 1, and m is 0; or (iii) l₁ is 1, l₂ is 1, and m is
 1. 10. Thephoto-destroyable quencher according to claim 1, wherein L² comprises asubstituted or unsubstituted C₁₋₃₀ alkylene group, a substituted orunsubstituted C₆₋₃₀ arylene group, a substituted or unsubstituted C₇₋₃₀aralkylene group, or combination comprising at least one of theforegoing.
 11. A composition comprising: an acid-sensitive polymer; aphotoacid generator; and the photo-destroyable quencher of claim
 1. 12.A coated substrate comprising: (a) a substrate having one or more layersto be patterned on a surface thereof; and (b) a layer of the compositionof claim 11 disposed over the one or more layers to be patterned.
 13. Amethod of making a relief image, the method comprising coating asubstrate having a layer comprising an acid-sensitive polymer, aphotoacid generator, and a photo-destroyable quencher having Formula(I):

wherein X is S or I, each R⁰ is attached to X, and is independently aC₁₋₃₀ alkyl group, a polycyclic or monocyclic C₃₋₃₀ cycloalkyl group, apolycyclic or monocyclic C₆₋₃₀ aryl group, or a combination comprisingat least one of the foregoing, provided that at least one R⁰ is apolycyclic or monocyclic C₆₋₃₀ aryl group; r0 is 1 or 2, provided thatwhen X is I, r0 is 1, and when X is S, r0 is 2, wherein when X is S,groups R⁰ are optionally connected to each other so as to form a ring;and Ar is a substituted or unsubstituted divalent C₆-C₃₀ aromatic group;L¹ and L² are each independently a divalent C₁-C₃₀ linking groupoptionally comprising a heteroatom comprising O, S, N, F, or acombination comprising at least one of the foregoing heteroatoms; M is asubstituted or unsubstituted, divalent C₅-C₃₀ or greater monocyclic,polycyclic, or fused polycyclic cycloaliphatic group, optionallycomprising a heteroatom comprising O, S, N, F, or a combinationcomprising at least one of the foregoing; Y is an oxygen-containinganionic group, provided that when X is S, Y is C(═O)O, O, or SO₂NH; andl₁, l₂, and m are each independently an integer of 0 or 1, pattern-wiseexposing the composition layer to activating radiation; and developingthe exposed photoresist composition layer to provide a resist reliefimage.
 14. A photo-destroyable quencher having Formula (II-A):

wherein each R⁰ is independently a C₁₋₃₀ alkyl group, a polycyclic ormonocyclic C₃₋₃₀ cycloalkyl group, a polycyclic C₆₋₃₀ aryl group, amonocyclic C₆₋₃₀ aryl group substituted with halogen, or a combinationcomprising at least one of the foregoing, provided that at least one R⁰is a polycyclic C₆₋₃₀ aryl group or a monocyclic C₆₋₃₀ aryl groupsubstituted with halogen; groups R⁰ are optionally connected to eachother so as to form a ring; and Ar is a substituted or unsubstituteddivalent C₆-C₃₀ aromatic group; L¹ and L² are each independently adivalent C₁-C₃₀ linking group optionally comprising a heteroatomcomprising O, S, N, F, or a combination comprising at least one of theforegoing heteroatoms; M is a substituted or unsubstituted, divalentC₅-C₃₀ or greater monocyclic, polycyclic, or fused polycycliccycloaliphatic group, optionally comprising a heteroatom comprising O,S, N, F, or a combination comprising at least one of the foregoing; andl₁, l₂, and m are each independently an integer of 0 or
 1. 15. Acomposition comprising: an acid-sensitive polymer; a photoacidgenerator; and the photo-destroyable quencher of claim
 14. 16. A coatedsubstrate comprising: (a) a substrate having one or more layers to bepatterned on a surface thereof; and (b) a layer of the composition ofclaim 15 disposed over the one or more layers to be patterned.
 17. Amethod of making a relief image, the method comprising coating asubstrate having a layer comprising an acid-sensitive polymer, aphotoacid generator, and a photo-destroyable quencher having Formula(II-A):

wherein each R⁰ is independently a C₁₋₃₀ alkyl group, a polycyclic ormonocyclic C₃₋₃₀ cycloalkyl group, a polycyclic C₆₋₃₀ aryl group, amonocyclic C₆₋₃₀ aryl group substituted with halogen, or a combinationcomprising at least one of the foregoing, provided that at least one R⁰is a polycyclic C₆₋₃₀ aryl group or a monocyclic C₆₋₃₀ aryl groupsubstituted with halogen; groups R⁰ are optionally connected to eachother so as to form a ring; and Ar is a substituted or unsubstituteddivalent C₆-C₃₀ aromatic group; L¹ and L² are each independently adivalent C₁-C₃₀ linking group optionally comprising a heteroatomcomprising O, S, N, F, or a combination comprising at least one of theforegoing heteroatoms; M is a substituted or unsubstituted, divalentC₅-C₃₀ or greater monocyclic, polycyclic, or fused polycycliccycloaliphatic group, optionally comprising a heteroatom comprising O,S, N, F, or a combination comprising at least one of the foregoing; andl₁, l₂, and m are each independently an integer of 0 or 1, pattern-wiseexposing the composition layer to activating radiation; and developingthe exposed photoresist composition layer to provide a resist reliefimage.